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Divergent responses of runoff to climate change in the upper basins of the Third Pole dominated by westerlies and monsoon

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Science China Earth Sciences 2024年第8期67卷 2592-2614页

作者： Qikai sun Fengge SU he sun State Key Laboratory of Tibetan Plateau Earth System Environment and Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100101China

The diverse climates,distribution of snow and glaciers,and geographic locations directly affect the runoff response to climate change in the upper basins of the Third *** present,a comprehensive analysis of runoff variations and their distinct responses to climate change in the westerlies-and monsoon-dominated upper basins is still *** study comprehensively analyzed annual runoff variations in westerlies-dominated basins(the upper basins of the Aksu(UAKS),Syr Darya(USRD),Yarkant(UYK),Hotan(UHT),Amu Darya(UAMD),and Indus(UI))and monsoon-dominated basins(the upper basins of the Yangtze(UYA),Yellow(UYE),Lancang(ULC),Nujiang(UNJ),and Yarlung Zangbo(UYZ))of the Third Pole from 1961 *** multi-source meteorological data and large-scale circulation factors,this study investigated the divergent responses of runoff in the upper basins to climate change,and explored the large-scale circulation mechanisms underlying runoff variations in these upper *** results showed that:(1)The annual runoff in the majority of upper basins(except for the UYE and UYZ)exhibited an increasing trend,and the annual runoff in the UAKS,UYK,and UI showed a significant increasing trend from1961 to *** annual runoff in the upper basins of the Third Pole changed abruptly from decreasing to increasing between the 1980s and 2000s,with the exception of the UYE.(2)The runoff in the monsoon-dominated upper basins has been controlled primarily by changes in precipitation over the past 55 *** contrast,the runoff in the westerlies-dominated upper basins exhibited three distinct long-term responses to climate change:temperature-dominated(UYK and UHT),precipitation-dominated(USRD and UAMD),and the combined influence of precipitation and temperature(UAKS and UI).Since the 1960s,the sensitivity of runoff to warm season temperature changes in the most westerlies-dominated upper basins has decreased,while the response of runoff to precipitation changes has intensified.(3)The stud

关键词： Upper basins of the Third Pole Climate change Westerlies and monsoon Runoff variations Large-scale circulation factors

FEM Analysis of Effect of Die Angle on Tube Inversion Forming Process under Conical Die

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Journal of Materials Science & Technology 2003年第z1期19卷 234-236页

作者： Zhichao sun he YANG College of Materials Science and Engineering Northwestern Polytechnical University Xi′an 710072 China College of Materials Science and Engineering Northwestern Polytechnical University Xi′an 710072 China

Tube inversion including free deformation under conical die is an advanced forming process for manufacturing complicated thin-walled parts with high strength/weight ratio, high efficiency, and good flexibility for size ***, the successful reality of forming process, the change of deforming mode and shape and size of part formedare mainly on the die angle. Based on the analysis of the forming process, the model of rigid-plastic FEM (finiteelement method) is established and a numerical simulation system is developed. The effect of die angle on the tubeinversion forming process is investigated with the code developed. The results of the effect of half die angle on shapeof free deformation zone and on deforming load are obtained. There is an optimal die angle (about 75 deg), whichmakes the forming load minimum.

关键词： Tube inversion under conical die, Rigid-plastic FEM, Die angle, Free deformation

Applications of proteomics in hepatic diseases research

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Science China(Life Sciences) 2004年第2期47卷 101-106页

作者： sun Wei he Fuchu Laboratory of Systems Biology Beijing Institute of Radiation Medicine Beijing 100850 China Laboratory of Systems Biology Beijing Institute of Radiation Medicine Beijing 100850 China

Proteomics has become an important part in the leading research area and been widely used in the disease-associated study. In hepatic research field, proteomics could be ap-plied in study of hepatic diseases including liver cancer, cirrhosis and hepatotoxicities, etc. Sig-nificant proteins could be identified as biomarkers, drug targets and clues for pathogenesis illu-mination.

关键词： proteomics, hepatic diseases.

Solving Lyapunov equation by quantum algorithm

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Control Theory and Technology 2017年第4期15卷 267-273页

作者： he sun Jing Zhang 1. Department of Automation Tsinghua University Beijing 100084 China

Lyapunov equation is one of the most basic and important equations in control theory, which has various applications in, e.g., stability analysis and robust analysis of linear control systems. Inspired by the recent progresses of quantum algorithms, we find that solving Lyapunov equation can be exponentially accelerated by quantum algorithms rather than traditional classical algorithms. Our algorithm is more efficient especially when the system matrix is sparse and has a low condition number. The results presented in this paper open up new dimensions of research in controlling classical system by quantum information processors, which has rarely been considered in the existing literature.

关键词： Quantum control linear Lyapunov equation large-scale complex system

A Study on Modeling and Optimization of Memory Systems

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Journal of Computer Science & Technology 2021年第1期36卷 71-89页

作者： Jason Liu Pedro Espina Xian-he sun School of Computing and Information Sciences Florida International UniversityMiamiFL 33199U.S.A Department of Computer Science Illinois Institute of TechnologyChicagoIL 60616U.S.A

Accesses Per Cycle(APC),Concurrent Average Memory Access Time(C-AMAT),and Layered Performance Matching(LPM)are three memory performance models that consider both data locality and memory assess *** APC model measures the throughput of a memory architecture and therefore reflects the quality of service(QoS)of a memory *** C-AMAT model provides a recursive expression for the memory access delay and therefore can be used for identifying the potential bottlenecks in a memory *** LPM method transforms a global memory system optimization into localized optimizations at each memory layer by matching the data access demands of the applications with the underlying memory system *** three models have been proposed separately through prior *** paper reexamines the three models under one coherent mathematical *** specifically,we present a new memorycentric view of data *** divide the memory cycles at each memory layer into four distinct categories and use them to recursively define the memory access latency and concurrency along the memory *** new perspective offers new insights with a clear formulation of the memory performance considering both locality and ***,the performance model can be easily understood and applied in engineering *** such,the memory-centric approach helps establish a unified mathematical foundation for model-driven performance analysis and optimization of contemporary and future memory systems.

关键词： performance modeling performance optimization memory architecture memory hierarchy concurrent average memory access time

I/O Acceleration via Multi-Tiered Data Buffering and Prefetching

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Journal of Computer Science & Technology 2020年第1期35卷 92-120页

作者： Anthony Kougkas Hariharan Devarajan Xian-he sun Department of Computer Science Illinois Institute of TechnologyChicago 60616U.S.A

Modern High-Performance Computing(HPC)systems are adding extra layers to the memory and storage hierarchy,named deep memory and storage hierarchy(DMSH),to increase I/O *** hardware technologies,such as NVMe and SSD,have been introduced in burst buffer installations to reduce the pressure for external storage and boost the burstiness of modern I/O *** DMSH has demonstrated its strength and potential in ***,each layer of DMSH is an independent heterogeneous system and data movement among more layers is significantly more complex even without considering *** to efficiently utilize the DMSH is a subject of research facing the HPC ***,accessing data with a high-throughput and low-latency is more imperative than *** prefetching is a well-known technique for hiding read latency by requesting data before it is needed to move it from a high-latency medium(e.g.,disk)to a low-latency one(e.g.,main memory).However,existing solutions do not consider the new deep memory and storage hierarchy and also suffer from under-utilization of prefetching resources and unnecessary ***,existing approaches implement a client-pull model where understanding the application's I/O behavior drives prefetching *** towards exascale,where machines run multiple applications concurrently by accessing files in a workflow,a more data-centric approach resolves challenges such as cache pollution and *** this paper,we present the design and implementation of hermes:a new,heterogeneous-aware,multi-tiered,dynamic,and distributed I/O buffering *** enables,manages,supervises,and,in some sense,extends I/O buffering to fully integrate into the *** introduce three novel data placement policies to efficiently utilize all layers and we present three novel techniques to perform memory,metadata,and communication management in hierarchical buffering ***,we demonstrate the benefits

关键词： I/O buffering heterogeneous buffering layered buffering deep memory hierarchy burst buffers hierarchical data prefetching data-centric architecture

Recycling rare earth from ultrafine NdFeB waste by capturing fluorine ions in wastewater and preparing them into nano-scale neodynium oxyfluoride

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Journal of Rare Earths 2022年第5期40卷 815-821,I0005页

作者： he sun Tuoyao Wang Chengxiang Li Yusheng Yang Department of Chemistry Baotou Teachers’CollegeBaotou 014030China School of Energy and Environment Inner Mongolia University of Science and TechnologyBaotou 014010China Key Laboratory of Integrated Exploitation of Bayan Obo Multi-Metal Resources School of Material and MetallurgyInner Mongolia University of Science and TechnologyBaotou 014010China Collaborative Innovation Center of Integrated Exploitation of Bayan Obo Multi-Metal Resources Inner Mongolia University of Science and TechnologyBaotou 014010China

Ultrafine NdFeB waste is a relatively clean waste produced during NdFeB magnet *** wastewater is a common type of industrial wastewater,such as stainless steel pickling *** this work,rare earth element neodynium was recycled from ultrafine NdFeB waste by capturing fluorine ions in the fluorine-containing wastewater and prepared into neodynium *** reaction process was investigated through UV-Vis-NIR,thermogravimetry/differential thermogravimetry(TG/DTG),X-ray diffraction(XRD)and X-ray photoelectron spectroscopy(XPS).The neodymium hydroxide in the ultrafine NdFeB waste reacted with fluorine ions to form Nd(OH)_(2) F,and Nd(OH)_(2) F was then transformed into neodymium oxyfluoride after *** formed neodymium oxyfluoride is found to be particles with rhombohedral structure and a particle size of around 50 *** reaction kinetics of forming Nd(OH)_(2) F was *** reaction kinetic equation was established and the reaction activation energy was *** effect of fluorine ion concentration on the reaction rate and products was *** results show that the reaction rate increases with the increase of fluorine ion concentration in the range of 0.01-1.5 mol/L,but it has little *** addition,the fluorine ion concentration affects the crystallinity of formed neodymium *** recycling process not only realizes the sustainable utilization of rare earths,but also reduces the concentration of fluorine ions in the fluorine-containing wastewater,achieving two goals with one stone.

关键词： Recycling Ultrafine NdFeB waste Capturing fluorine ions Neodymium oxyfluoride Rare earths

Design of S-band re-entrant cavity BPM

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Nuclear Science and Techniques 2009年第3期20卷 133-139页

作者： LUO Qing sun Baogen he Duohui National Synchrotron Radiation Laboratory School of Nuclear Science and Technology University of Science and Technology of China Hefei 230029 China

An S-band cavity BPM is designed for a new injector for HLS (hefei Light Source). It consists of two cavities that work on 2448 MHz: a re-entrant position cavity tuned to TM110 mode and a reference cavity tuned to TM010 mode. Cut-through waveguides are used as pickups to suppress the monopole signal. Simulations with different assumption of dimension change are performed to evaluate errors caused by mechanical error and give general tolerance. Design of electronics is given. Theoretical resolution of this design is 31 nm.

关键词： BPM 电子学单极信号理论

A semi-analytical multi-harmonic balance method on full-3D contact model for dynamic analysis of dry friction systems

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Chinese Journal of Aeronautics 2024年第2期37卷 309-329页

作者： he sun Dayi ZHANG Yaguang WU Qingyang SheN Dianyin HU Research Institute of Aero-Engine Beihang UniversityBeijing 100191China School of Energy and Power Engineering Beihang UniversityBeijing 100191China Beijing Key Laboratory of Aero-Engine Structure and Strength Beijing 100191China Sino-French Engineering School Beihang UniversityBeijing 100191China AECC Sichuan Gas Turbine Research Establishment Chengdu 610500China

Dry friction damping structures are widely-used in aero-engines to mitigate *** nonlinear nature of friction and the two-dimensional in-plane motion on the contact interface bring challenges to accurately and efficiently predict the forced response of frictionally damped *** state-of-the-art Multi-Harmonic Balance Method(MHBM)on quasi-3D contact model in engineering cannot precisely capture the kinematics on the friction interface although the efficiency is *** full-3D contact model can describe the constitutive relationship of the interface in a more accurate manner;however,the efficiency and convergence are not guaranteed for large-scale *** this paper,a semi-analytical MHBM on full-3D contact model is *** original Trajectory Tracking Method(TTM)for evaluating the contact force is reformulated to make the calculation more concise and the derivation of the Analytical Jacobian Matrix(AJM)*** on the chain rule of derivation,the AJM which is the core to upgrade the performance is *** a shrouded blade finite element model,the accuracy and efficiency of the proposed method are compared with both the MHBM on full-3D contact model with numerical Jacobian matrix and the MHBM on quasi-3D contact model with *** results show that the AJM improves significantly the efficiency of the MHBM on full-3D contact *** time cost of the proposed method is in the same order of magnitude as that of the MHBM on quasi-3D contact *** also confirm that the full-3D contact model is necessary for the dynamic analyses of shrouded *** one uses the quasi-3D model,the estimation relative error of damping can even reach 31.8%in some *** addition,the AJM also brings benefits for stability *** is highly recommended that engineers use the MHBM on full-3D contact model for the dynamic analysis and design of shrouded blades.

关键词： Dry friction damping Multi-harmonic balance method Trajectory tracking method Jacobian matrix Shrouded blade